Method for managing water channel systems

ABSTRACT

A method of managing a storm water or other open channel system wherein (a) the system is divided into a plurality of channel segment lengths for evaluation; (b) an inventory based upon a standardized set of items is conducted for each channel segment to identify any and each of the items which exist in the channel segment; and (c) a standardized channel condition index value is determined for each channel segment based upon the inventory.

FIELD OF THE INVENTION

The present invention relates to methods of managing open water channel systems.

BACKGROUND OF THE INVENTION

A need exists for an effective method which can be used by municipalities, counties, companies, landowners, and others for managing open water channel systems. Such systems typically comprise a collection of inter-connected channels which must be inspected, serviced, maintained, and sometimes improved. A method is needed which will be effective for assisting the municipality or other entity in identifying, prioritizing, and organizing individual service projects, maintenance projects, and capital improvement projects throughout the channel system.

Examples of service needs within an open channel system commonly include, but are not limited to, dealing with problems related to trees, brush, undergrowth, erosion, scour, sedimentation, debris accumulation, and other natural conditions. In addition to such service needs, channel improvement structures often need to be repaired, replaced, or added to the channel system. Examples of typical channel improvements include, but are not limited to, concrete side slopes and/or bottoms, trickle channels, rip rap, gabion, and retaining walls.

A need exists for an open channel management method which will not only assist in organizing and prioritizing service, maintenance, and improvement projects in terms of addressing flow problems and improving flow conditions within the channel system, but which will also account for the effect or potential effect of such channel conditions or improvements on any adjacent over bank properties, adjacent infrastructure, and public or private utilities. A need also exists for a system which will enable communities or other entities to easily and efficiently obtain an overview of the condition of the open channel systems in their care and to quickly prepare visual and tabular reports in the particular form desired.

SUMMARY OF THE INVENTION

The present invention satisfies the needs discussed above. In one aspect, there is provided a method of managing a system of open channels for evaluating channel conditions, servicing the open channels, maintaining the open channels, improving the open channels, or a combination thereof. The method comprises the steps of: (a) dividing the system of open channels into a plurality of channel segments for evaluation; (b) conducting for each channel segment an inventory based upon a standardized set of items to identify any and each of said items existing in the channel segment; and (c) determining a standardized channel condition index value for each channel segment based upon said items existing in the channel segment.

In the inventive method, the step of determining a standardized channel condition index value for each channel segment also preferably includes applying standardized weighting multipliers to said items existing in the channel segment to provide a set of weighted item values for the channel segment. In addition, the step of determining the standardized channel condition index value for each channel segment preferably comprises calculating a total of the set of weighted item values for the channel segment. Further, the step of determining a standardized channel condition index value for the channel segment also preferably includes dividing the total of the set of weighted item values for the channel segment by a length of the channel segment. It is also preferred that the inventive method include the step of ranking the channel segments according to the standardized channel condition index values for the channel segments.

In another aspect, the present invention provides a method of managing a system of open channels for evaluating channel conditions, servicing the open channels, maintaining the open channels, improving the open channels, or a combination thereof, wherein the method comprises the steps of: (a) dividing the system of open channels into a plurality of channel segments for evaluation; (b) conducting for each channel segment an inventory based upon a standardized set of items to identify any and each of said items existing in the channel segment; (c) assigning ratings to at least a portion of said items existing in the channel segments based upon standardized ratings scales; and (d) determining a standardized channel condition index value for each channel segment based upon said items existing in the channel segment and the ratings assigned to the portion of said items. The step of determining a standardized channel condition index value for each channel segment preferably also includes employing standardized weighting multipliers to the items existing in the channel segment to provide a set of weighted item values for the channel segment, wherein the standardized weighting multipliers applied to the above-mentioned portion of the items are dependent upon the ratings assigned to the portion of the items.

In another aspect, there is provided a method of managing a system of open channels comprising the steps of: (a) dividing the system of open channels into a plurality of channel segments; (b) conducting for each said channel segment an inventory based upon a standardized set of items to identify any and each of the items existing in the channel segment; and (c) assigning ratings to at least a portion of the items existing in the channel segments based upon standardized ratings scales and instructions.

Further aspects, features, and advantages of the present invention will be apparent to those in the art upon examining the accompanying drawings and upon reading the following detailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of an embodiment of the inventive channel management method.

FIG. 2A is an example of first portion of a standardized channel segment inspection form preferred for use in the present invention.

FIG. 2B is a second portion of the standardized channel segment inspection form.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a comprehensive method for inspecting, quantifying, tabulating and analyzing the different elements which make up natural and improved channels within a municipality or other area. The method provides: (a) a methodology for subdividing the open channels into individual reaches or other segments with similar properties; (b) a standardized methodology for performing a field inspection and inventory of the individual segments using a consistent, standardized procedure for identifying relevant elements and assigning condition state values for the elements found in each segment; (c) a database using, e.g., Microsoft Access or other system to store the data accumulated for each segment; (d) the ability to run queries within the database for retrieving and presenting the data in a variety of meaningful ways; and (e) a procedure for geo-referencing the individual segments in the database so that their attributes can be mapped and visualized (e.g., using a graphic information system (GIS) system). Moreover, in the inventive method, a standardized channel condition index value is determined for each channel segment. The standardized channel condition index values for the channel segments can be used along with the other data gathered and the analyses and reports generated by the inventive system for evaluating and prioritizing needed service projects, maintenance, and capital improvements throughout the entire open channel system.

If an adequate mapping system does not already exist, a preferred initial step of the inventive method is to accurately define the channel centerlines and establish a river stationing system for the area in question. As will be described more fully hereinbelow, current topographical aerial photos or other sources or materials can be used for tracing the channel centerlines. The aerial photos, with topographic information, can be fed into an AutoCAD system and the flow lines of the system channels can be traced from their downstream confluence to their upstream limit.

The overall channel lengths are preferably then divided into manageable reaches (i.e., segments) and a standardized naming procedure is applied. If a system within a municipality or other area has already been broken down into flood management areas or other divisions, these divisions can often provide the starting point for dividing the channel system and can also form the basis for the naming procedure.

For example, if a particular section of the channel system is known as Swift Creek (SC) basin and the SC basin includes 16 flood management areas, these flood management areas could be designated as SC-01 through SC-16. Some or all of these flood management areas could then be further divided into a plurality of reaches/segments. These divisions will preferably coincide with significant differences in channel configurations and characteristics existing within the flood management area. Thus, for example, the flood management area SC-05 might be divided into three segments (SC-05-A through SC-05-C) wherein the first segment SC-05-A might be a segment having concrete side slopes, the next segment SC-05-B, might be a natural channel segment with no improvements, and the next segment, SC-05-C, might be a segment having rip rap side slopes.

In some cases, significant changes in channel configurations can be discerned by examining aerial photographs. Thus, it will be possible in many cases to at least begin the division of the channel system into relevant segments using aerial photos and/or other drawings, information, or data. However, it will typically be necessary in most cases to confirm at least some of the segment boundaries during the field inspections of the channel segments discussed hereinbelow.

As will be described below, the inventive method employs a standardized inventory procedure for inspecting each of the channel segments of the open channel system and for determining a standardized channel condition index value for each segment. The standardized inventory is based, at least in part, on a predetermined set of possible conditions, features, and other items which may be present in the channel segments. At least some of the items contained in the inventory list could also serve as examples of possible bases for distinguishing different portions of a given channel system for dividing the channel system into manageable segments.

A flow chart outlining an embodiment of the inventive channel management method is provided in FIG. 1. In the inventive method, a field inspection is preferably conducted using a standardized form which includes a list of predetermined items relevant to determining the relative condition of each segment in question. A separate copy of the form will preferably be used for inspecting each individual segment and the personnel conducting the inspection will identify the type and quantity of each item listed on the form which is/are found in the segment.

An example of a standardized inspection form for use in the inventive method is provided in FIGS. 2A and 2B. The items listed on the form are used for determining the condition of the channel segment in question and for ranking all of the channel segments within the channel system with regard to the priority of needed service, maintenance, and improvements. The types of items contained in the list include: adjacent land use factors; adjacent structures in the flood plane; adjacent over-bank properties affected by the channel condition; infrastructure items affected by the channel condition; public utilities; private utilities; natural channel conveyance conditions; and the condition of existing channel improvements. The form also includes standardized ratings scales for most of the items listed.

The first block of the standardized channel reach inspection form pertains to the precise identification of the channel segment in question and will preferably be completed in accordance with the standardized procedures and criteria set forth in Table I.

TABLE I Standardized Instructions for Completing the Reach/Segment Identification Block of the Standardized Inspection Form Creek Name of Creek FMA Flood Management Area (for example, SC-1, SC-2, etc.) Reach ID Reach designation (A, B, C, etc.) Description Provide a brief description of the Reach. Put in anything pertinent, for example, “Natural Channel,” “Subdivision Improved Channel,” :Harvard Avenue RCB,” etc. Council District From Council District Map Atlas Sheet From the Storm Sewer Atlas Sheet Inspection Date Date of field inspection Insp. By List the team members of the field inspection crew Does the City Enter Yes or No depending on whether or not the City Perform performs major maintenance functions on this reach. Maintenance Note: the City may perform major maintenance on this functions even if not responsible for routine mowing Channel Reach? and clearing. Access Describe if access is available to the channel reach by heavy equipment. Enter “by ramp on left bank, ” “none,” “across yard,” etc.

The next block of the reach/segment inspection form pertains to the description of the reach in question and will preferably be completed in accordance with the standardized procedures and criteria set forth in Table II.

TABLE II Instructions For Completing the Reach/Segment Description Block of the Standardized Reach Inspection Form Reach Enter information about the reach being inspected. Description Information includes the upstream and downstream reach section number that is equal to the channel centerline stationing. D/S Sec ft Down Stream section # of the Reach, taken from the plot which shows the channel centerline and stationing Descr. Brief description of the Down Stream section, for example, “beginning of rip-rap,” “beginning of natural channel,” “FMA boundary,” etc. U/S Sec # Up Stream section # of the Sub-Reach, taken from the plot which shows the channel centerline and stationing Descr. Brief description of the Up Stream section, for example, “end of concrete side slopes,” “end of gabion on left bank,” “FMA boundary,: etc. Computed U/S Sec #minus D/S Section #. This gives the Channel Length Sub-Reach channel length.

The next block of the standardized channel segment inspection form pertains to the identification and characterization, by percent, of the type of adjacent land use for the segment in question. This block of the form will preferably be completed in accordance with the standardized procedures and criteria set forth in Table III.

TABLE III Instructions For Completing The Adjacent Land Use Block of the Standard Reach/Segment Inspection Form Adjacent Land Enter the percentage of the reach that has the following Use for This land use types on the adjacent overbanks. The land use Reach by type on both overbanks should be calculated. For Percent example: the left overbank is Single Family (50%), and half of the right overbank is Multi Family (25%), and half is Open (25%). Single Family Single family residential neighborhood, or individual housing Multi Family Apartment buildings, duplexes, including parking lots, etc. Commercial/ Any commercial or industrial developments, including Industrial parking lots. Open/ Open fields without structures, like parks, golf courses, No Structures vacant lots, etc.

The next block of the standardized inspection form pertains to the number and type of structures adjacent to the segment in question which are in either a regulatory floodplain or a FEMA floodplain. This block of the form will preferably be completed in accordance with the standardized procedures and criteria set forth in Table IV.

TABLE IV Instructions For Completing the Adjacent Structures in Floodplain Block of the Standardized Reach Inspection Form Number of Adjacent Enter the number of insurable structures (excluding Structures in detached garages, outbuildings, etc.) that are within Floodplain the Regulatory and FEMA floodplains. Single Family Single family residential structures Multi Family Multi family apartment buildings, duplexes, etc. Commercial/ Any commercial or industrial building, include Industrial churches in this category Public Buildings Any public building

The next block of the standardized channel reach inspection form pertains to the number and type of adjacent overbank properties affected by the channel condition. A rating scale of “slightly affected,” “moderately affected,” or “highly affected” is provided for each overbank property item identified. This block of the standardized form will preferably be completed in accordance with the standardized procedures and criteria set forth in Table V.

TABLE V Instructions For Completing The Adjacent Overbank Properties Block Of The Standardized Reach/Segment Inspection Form Number of Adjacent Note: Enter the number of properties that are adversely affected by the Overbank Properties channel condition. Enter only structures that are “Slightly,” Affected by Channel “Moderately,” or “Highly,” affected. Do not enter structures that are Condition remote from the channel bank and not adversely affected. Slightly Moderately Highly Affected Affected Affected Houses Immediately adjacent Erosion or sloughing of Erosion or sloughing Apartment/Condo to the channel bank, the channel bank may of the channel bank Buildings even if the bank is soon endanger the is an immediate Detached Garages/Out stable. structure. danger to the Buildings structure. Yards Count any yard that is Erosion of the channel Erosion of the immediately adjacent bank has encroached channel bank is to the top of the onto the yard. sever and has greatly channel bank, even if encroached onto the the bank is stable yard. Fences Fence on top of Fence posts are exposed Fence posts are channel bank, and may due to erosion of the exposed; fence is need a little work soon channel bank. Needs leaning and may to protect it. attention to halt the soon fall down. damage, but is not in Needs immediate immediate danger of attention or has collapsing. already fallen. Other Appurtenances Garden sheds, brick/stone cookers, gazebos, green houses, etc. Rate the same as Houses Commercial/Industrial Any commercial or industrial building, include Churches in this category. Buildings Rate the same as Houses. Public Buildings Any public building. Rate the same as Houses. Other Buildings Any building not described above. Rate the same as Houses Parking Lots Parking lot is Erosion or sloughing of Erosion or sloughing immediately adjacent the channel bank may of the channel bank to the channel bank, soon endanger the is an immediate even if the bank is parking lot. danger to the stable parking log.

The next block of the standardized channel segment inspection form pertains to the type and number of infrastructure items affected by the channel condition. A standardized rating scale of “not affected,” “slightly affected,” “moderately affected,” or “highly affected” is provided for each infrastructure item identified. This block of the channel segment inspection form will preferably be completed in accordance with the standardized procedures and criteria set forth in Table VI.

TABLE VI Instructions For Completing The Infrastructure Items Affected Block of the Standardized Reach/Segment Inspection Form Number of Infrastructure Items Affected by Channel Condition Each of the following items found within the channel reach should be counted and placed in the appropriate “condition state” category Not Slightly Moderately Highly Affected Affected Affected Affected Side Headwall/Outfall Headwall/Outfall in Downstream face Headwall/outfall Joint separation Include: good, stable of apron is undercut and/or separation Only count storm sewer condition. headwall/outfall by erosion. No of headwall from headwalls/outfalls on the apron is exposed, joint separation or storm sewer pipe. side of the main channel. but not undercut. headwall failure. Headwall or apron Count storm sewer May be erosion Serviceable rotated or fallen headwalls, pipe ends w/o behind wings, but condition, but in in. headwalls, and outfalls for generally in need of work to Headwall/outfall tributaries. serviceable stop the has failed. condition. deterioration. Weir/Blocks/Drop No defects. Chipping, Severe chipping, Structure has Include: Structure is in good spalling, cracking, spalling, cracking, failed. Severe Weirs working order. or other minor or other defects defects and/or Energy Dissipaters defects. There is are present. missing sections. Drops in channel elev. no rotation or -or- settlement. Structure has Footing may be rotated and/or exposed but is not shows some undercut. settlement. Structure in -or- serviceable Footing is condition. exposed and undercut. Roadway (LF) No defects. Roadway edge or Roadway edge or Roadway edge or Count the length of Roadway Roadway is in good curb shows slight curb shows curb has failed. that is immediately condition. Curb, if defects. May be moderate defects. Bank erosion has adjacent to the creek present in good chipping, spalling, Bank erosion has caused severe channel. condition. or “drop-off” undercut the edge spalling or present, but it of the roadway sloughing that does not affect the resulting in represents a serviceability of spalling or “drop- hazard to traffic the roadway. off.” There is an on the roadway. inconvenience to traffic on the roadway. Bridge Abutment Bridge abutment in Abutment in good Abutment may Abutment has Count each bridge abutment good condition with overall condition, show cracks and severe cracking, in the reach. no visible defects. but there are slight exposure of exposure and defects. May be footing. undercutting of some exposure of Abutment in footing, the footing and overall shifting/rotation minor cracking. serviceable that affects its condition. No function. shifting or rotation. Bridge Pier No defects visible. Bridge pier in Cracking and/or Bridge pier may Count each individual bridge good serviceable spalling may be have settled or pier as one. condition. May more pronounced. rotated enough to Count each culvert interior be some spalling Scour may have endanger the wall as one. or minor cracking. exposed the bridge structure. Scour may have footing. No Spalling and/or exposed the settlement or cracking are footing. rotation. severe. Scour may have undercut the footing. Culvert Wingwall Wingwall has no Wingwall has Wingwall has Wingwall has Includes: defects. slight cracking or cracking thru the separated from the Each culvert wingwall spalling. Footing wall or severe bridge structure, found on a structure that may be exposed, spalling. Footing or rotated such crosses the main channel but is not may be undercut. that its function is centerline. undercut. No Wingwall is still compromised. rotation or functional. settlement. Culvert Apron/End Apron/End in good Apron/End shows Apron/End has Apron/End has Includes: condition with no slight spalling or more severe cracking or Each culvert apron or defects. End is not cracking. End cracks and/or spalling so severe end of culvert if apron is scoured. may be exposed, spalling or has that the structure not present. Only on but is not been undercut by has failed. Apron structures that cross the undercut. scour. may have main channel centerline. separated from the culvert and settled or rotated. Pipe Culvert Pipes and headwall Pipes and Pipes and head- Pipe culvert Includes: in good condition. headwalls may wall have system has Each pipe culvert found No defects. have slight significant crack- significant on-line with the main spalling of edges. ing and/or spall- settlement, or channel centerline. Headwall is solid ing. Headwall has significant defects and effective. No significant that affect the settlement. defects. There function of the may be slight system. settlement. Low Water Crossing Low water crossing Low water Serviceability of Low water Includes: in good condition. crossing still fully the low water crossing is not Each low water crossing that No visible defects functional, but crossing is functional due to crosses the main channel that affect the there are slight affected by erosion or centerline. structures' defects in the erosion, or a deterioration. condition. material making deterioration of up the crossing. the material No settlement of making up the roadway or low crossing. flow pipes. Other Structure Structure is in Structure has Structure has Structure has Include: perfect condition slight defects, but moderate defects failed and is not Any other structure without defects. the functionality is that affect the functional. found in the channel that not affected. functionality, but is not described above. it is still serviceable.

The next block of the standardized inspection form pertains to any public or private utilities associated with the channel segment in question and will preferably be completed in accordance with the standardized procedures and criteria set forth in Table VII.

TABLE VII Instructions For Completing The Public And Private Utilities Block Of The Reach/Segment Inspection Form Public Utilities Public utilities in this program include sanitary sewer lines, manholes, and waterlines. There are no condition states for the exposed utility, only the linear footage of the exposed line, or the number of affected manholes. Use the plotted maps to help locate the general alignment and look for exposed lines. Sanitary Sewer Line Count the total linear footage of sanitary sewer line that is exposed (Exposed) LF within the channel banks. Sanitary sewer line is usually made of Reinforced Concrete Pipe (RCP), cast iron pipe, or red clay pipe. Sometimes sanitary sewer lines will be fully encased in concrete as it crosses the bottom of the channel. In this case, count the length of concrete encasement. The linear footage of exposed service lines from the main line should also be counted. These lines are usually 4″ Cast Iron Pipe or may be PVC, and run from the main line across the channel to a residence. Count the total linear footage of exposed line, even if the line is intentionally exposed (set in concrete thrust blocks, or encased in concrete at the bottom of the channel). # of Sanitary Sewer Manholes Count the number of sanitary sewer manholes that are exposed. Exposed Manholes are usually cylindrical, pre-cast concrete, or brick with grouted coating. There should be a manhole cover on top stamped “Sanitary Sewer.” Count each manhole that is exposed within the channel banks. Water Line Exposed (LF) Count the total linear footage of water line exposed within the channel banks. Waterlines in the channel are generally made of black ductile iron pipe, although PVC pipe may also be seen. Usually, waterlines crossing the channel will be found parallel to roadway crossings, but not always. Waterlines may be confused with gas lines, so refer to the plotted maps for general alignments. Private Utilities Private utilities in this program include gas lines, gas meters, buried electric lines, telephone (utility) poles, telephone risers, telephone lines, cable TV risers, cable TV lines, etc. There are no condition states for the exposed utility, only the number of exposed lines, or the number of utility poles, risers, meters, etc. # of Gas Line Exposures Count the number of gas lines exposures. Gas lines could be made of black pipe, ductile iron pipe, or orange Poly Propylene Flexible Pipe. The pipe may be painted black, yellow or orange. The pipeline may cross the channel or run parallel to it. Count each exposure of a gas line, no matter how long, as one exposure; do not count the linear footage of the line. Also, count an exposed gas meter as one exposure. # of Electric Line Exposures Most electric line exposures will be a utility pole within the channel. Count each pole within the channel as one exposure. Also count the number of electric line exposures. Electric lines are generally encased in gray PVC pipe, or gray Romex line. Only count a single line as one exposure. Do not count the linear footage of the exposed line. # of Other Utility Exposures Other utility exposures include cable TV lines, telephone lines, telephone risers, etc. Count each cable, riser, etc., as one exposure. When unable to positively determine the nature of the exposed element, put it in this category.

The next block of the standardized inspection form pertains to the number and type of natural channel conveyance conditions identified for the segment in question. A rating scale pertaining to the condition of trees having exposed roots or which have fallen or are in immediate danger of falling is provided. A standardized rating scale of “slight,” “moderate,” and “severe” is provided for other condition items listed in the block. This block of the form will preferably be completed in accordance with the standardized procedures and criteria set forth in Table VIII.

TABLE VIII Instructions For Completing The Channel Conveyance Condition Block Of The Standardized Reach/Segment Inspection Form Channel Conveyance Condition This category includes naturally occurring elements that affect the conveyance of water through the channel. Trees within the channel will be categorized and individually counted. In addition, the linear footage, along the centerline of the channel, of other naturally occurring elements will be counted and classified. Not Counted Do not count trees that are less than 6 in. diameter. Do not count trees that have adequate protection at the roots, either natural earth, or stones, or timbers, etc. # of Trees with Exposed Count the number of trees within the reach that have exposed roots and Roots are within the channel banks. Roots will be visible due to erosion, scour or sloughing. The tree itself will be stable, not undermined, and still solidly founded in the reach. Count the total number of trees in this classification that are within the reach. # of Trees in Immediate Count the number of trees within the reach that are in immediate Danger of Falling danger of falling. These trees will have scour that has cut under the main trunk of the tree, suspending the main trunk in the air. Also count trees in this category if it looks like a little more scour will cause the tree to fall. # of Trees Down in Channel Count the number of trees within the reach that are actually down in the channel, or are being kept up only by leaning on other trees. Newly fallen or main trunks that may have fallen a long time ago will be counted. The following 5 elements refer to natural conditions that obstruct the flow of water in the channel. The linear footage of each element should be counted along the centerline of the channel. For example, if Bottom Scour occurs in part of the channel for a length of 85 feet, place 85 in the appropriate classification. However, if bank erosion occurs on the left bank for a length of 50 feet, and also on the right bank for a length 25 feet, place a total of 75 in the appropriate classification. Only classifications of Slight, Moderate or Severe should be counted. Slight Moderate Severe Trees/Brush/Undergrowth Slight vegetation Vegetation Vegetation blocking Impeding Flow (LF) along the side of the encroaching on the the main channel, channel, but the main channel bottom. including the bottom. channel bottom is Moderate vegetation Or, heavy vegetation clear of any on both sides, or a on both sides obstruction. One side few mature trees encroaching well may be heavier than within the channel. within the channel the other side, but the bottom. overall obstruction is slight. Drift Accumulation Drift present, but not Considered a drift Again, considering a Impeding Flow (LF) in great quantity. pile that is of drift pile that is of Drift covers a small significant height. significant height, the percentage of the The drift is drift pile is Severe if channel cross section, considered Moderate it blocks over 50% of up to 10% if it blocks up to 50% the channel width. of the channel width. Bank Erosion/Scour (LF) Unprotected, bare Scour/erosion has Scour/Erosion is at Count the linear footage of earth limited to near progressed up the the top of the channel bank erosion or scour that the normal water line, bank, but has not yet bank, or, if near the occurs on each bank. but not very far up the reached the top of the top, the scour/erosion Therefore, the total bank bank. There may be channel. This is concave in erosion/scour could equal exposed roots but the erosion/scour is appearance. up to 2 times the total erosion/scour is not typically convex or Overhanging roots are reach length. very significant. flat in appearance. typical. Exposed roots are typical. Bottom Scour (LF) Located on the Bottom scour is Bottom scour is bottom of the evident and has threatening other channel, scour is barely undercut, or is channel components. evident, but not otherwise threatening Bottom scour is severe enough to other channel greater than 2′ deep, threaten any channel components. Bottom if measurable. components. Sides scour is less than 2′ are not undercut. deep, if measurable. Sediment Deposition (LF) Small amount of Sediment results in a Sediment has resulted sediment is visible on moderate loss of in a significant loss of the channel bottom, channel conveyance channel conveyance, but it results in no up to 25%. Typically, over 25%. Major loss of the channel's the sediment will vegetation is typical. ability to convey have slight vegetation water. Sediment is growing on it. composed of small rocks or sand with no vegetation.

The next block of the standardized inspection form pertains to the type, number, and condition of improvements already existing in the channel segment in question. A standardized rating scale of “not affected,” “slightly affected,” “moderately affected,” and “highly affected” is provided for each improvement item identified. This block of the inspection form will preferably be completed in accordance with the standardized procedures and criteria set forth in Table IX.

TABLE IX Instructions for Completing the Improved Channel Condition Block of the Standardized Reach/Segment Inspection Form Improved Channel (LF) Each of the following man-made items found within the channel reach should be counted, and placed in the appropriate “condition state” category. In all cases (except “End of Concrete Channel”), count the length of the man-made element along the bottom and each side, in-line with the channel centerline. For example, there could be rip-rap on one channel side, interlocking blocks on the bottom, and a masonry retaining wall on the other channel side. Place the total length of each element in the appropriate classification. If an element is in perfect condition place that length in the “Not Affected” condition. Slightly Moderately Not Affected Affected Affected Highly Affected Concrete Side Slopes Concrete Cracks visible, Cracking or Severe failure of Count the linear generally in but generally not spalling visible slab, including footage on each good condition. threatening the thru the slab, may rotation, channel side. No significant integrity of the be some settle- settlement or cracks, joints side slopes. No ment, rotation, or shifting of broken typically in good significant shifting of slab. or missing pieces condition. separation or Bare earth may be of the slab. Bare settlement. May visible, but slab earth and scour be slight spalling still more or less in visible in large visible. place. amounts due to failure of the slab. Concrete Bottom Concrete Cracks visible, Cracking or Severe failure of Count the linear generally in but generally not spalling visible the slab, including footage along the good condition, threatening the thru the slab, may rotation, channel bottom. No significant integrity of the be some settlement, or cracks, joints slab. No settlement, shifting of broken typically in good significant rotation, or or missing pieces condition. separation or shifting of slab. of the slab. Bare settlement. May Bare earth may be earth and scour be slight spalling visible, but the visible in large visible. slab still more or amounts due to less in place. failure of slab. End of Concrete Concrete end in Face of concrete Concrete end is Concrete end is Channel good, stable end exposed, but exposed and separated, sagging, Count the linear condition. End not undercut. undercut by rotated, or footage of the is flush with May be slight erosion. May be otherwise has exposed end of a flowline of cracking, but no cracking, failed. Slab end concrete lining on channel. No significant separation and has generally the bottom of the settlement, separation or settlement, but the failed. channel. spalling or settlement of end is generally cracking. slab. serviceable. Trickle Channel Trickle channel Cracks visible, Cracking or Severe failure of Count the linear generally in but generally not spalling visible the trickle channel footage along the good condition threatening the thru the trickle including rotation, channel bottom with no integrity of the channel. May be settlement, or significant trickle channel. some settlement, shifting of broken cracks, No significant rotation, or or missing pieces settlement or settlement or shifting, but the of the slab. undercutting. separation. trickle channel is Sections missing generally or completely serviceable. failed. Rip Rap Rip rap well Slight shifting Wide areas of Rip rap generally Count the linear positioned, and present or some visible earth failed, and not footage on each fully functional, missing pieces underneath due to protecting the channel side and No shifted, or resulting in slight shifting or missing earth as intended. along the channel missing pieces. visible bare earth pieces. The Bare earth with bottom. underneath. Rip condition of the widespread scour rap generally rip rap has resulted visible. Shifted or serviceable and in scour of missing pieces protecting as unprotected earth. widespread. intended. Rip Rap Grouted Grouted rip rap Slight cracking Cracking of the Severe failure of Count the linear well positioned, in the grout grout has resulted the grout with footage on each and fully present, but no in shifting, widespread channel side and functional. No missing pieces. separation or shifting, separation along the channel shifting or No significant undercutting of the or undercutting of bottom. missing pieces. separation or rip rap. Bare earth the rip rap. Bare Grout fully settlement. and scour may be earth and scour functional. Footing may be visible underneath. visible in large exposed, but amounts due to generally. failure of the serviceable. grouted rip rap. Gabion Gabions well Gabions may Sagging, bulging Gabion has failed. Count the linear aligned and show slight and/or rotation is Sagging, rotation footage on each fully functional. settlement, or present, but and/or bulging is channel side and No settlement or undercutting but baskets are not widespread. along the channel rotation. are generally torn or broken. Gabion baskets are bottom. Includes serviceable. No Undercutting or separated or torn, gabion mattress. rotation visible. erosion of spilling rocks. foundation typical. Interlocking Blocks The vast Slight settlement Settlement or Settlement or Count the linear majority of the or bulging is bulging has bulging has footage on each blocks are well visible, but the advanced to the resulted in channel side and aligned and individual blocks point that some widespread failure along the channel fully functional. are still inter- blocks are of the system. bottom. No settlement, connected. completely Bare earth and bulging or Individual blocks dislodged or scour is visible rotation of may be broken, missing. Bare underneath with individual but the whole earth is visible many blocks blocks. system is underneath. missing or broken. generally serviceable. Fabric Formed Mattress shows Slight cracking Cracking thru the The mattress Concrete no cracking, or patches mattress resulting system has failed. Count the linear settlement or visible. No in settlement or There are missing footage on each bulging. settlement or shifting of pieces. or rotated pieces channel side and bulging visible. Mattress pieces of mattress along the channel Footing may be still in place resulting in scour bottom. slightly undercut. providing of bare earth protection, but underneath. scour may be visible underneath. Retaining Wall, No defects Cracks may be Cracks are visible Retaining wall has Concrete visible. No visible in the in the wall. rotated so much, Count the linear cracks in the wall. No bulging Sagging or bulging or cracks, sagging footage on each wall. No or sagging. is present, but the or bulging is so channel side. settlement or Footing may be. wall has not failed. severe that the undercutting of exposed, but Footing may be wall has failed, or the footing. undercutting is undercut, cracked is in immediate slight, and or partially failing. danger of failure. footing is well founded. Retaining Wall, No defects Cracks may be Cracks are visible Sagging or bulging Masonry visible. No visible in the in the wall. has progressed to Count the linear cracks in the wall. No bulging Sagging or bulging the point that the footage on each wall. No or sagging. is present, but the retaining wall has channel side. settlement or Footing may be wall has not failed. failed. Masonry undercutting of exposed, but Footing may be blocks are the footing. undercutting is undercut, cracked dislodged, missing slight, and or partially failing. or collapsed. footing is well founded. Retaining Wall, All timber in Some loose, split Sagging and/or Sagging or bulging Timber good condition. or rotting bulging is present. has progressed to Count the linear Good timbers. Majority of the point that the footage on each foundation. No Foundation may timbers may be retaining wall has channel side. sagging or be suspect. No loose, split or failed. Timbers bulging. sagging or rotting. are dislodged or bulging. Undercutting or broken. erosion of foundation typical. Other Note type and condition state of other improved channel elements not listed above. Use the “Comments” section on the Form to provide more detail.

The data collected for all of the segments of the channel system will preferably be stored in a database created using Microsoft Access or other suitable software. The database will preferably contain one record for each of the channel segments. In addition to storing the data recorded on the inspection forms, the database will also preferably allow the user to include pictures taken during the field inspection and to view, query, and sort the data and generate reports using generally any criteria and format desired.

In order to facilitate and provide a reliable, standardized basis for categorizing and prioritizing all of the segments of the channel system based upon their respective condition states, a standardized channel condition index value is preferably calculated for each of the individual channel segments. The standardized channel index value will preferably be determined based upon the various items identified on the inspection form for the channel segment in question. This will preferably be accomplished by applying standardized weighting multipliers to each of the items identified on the inspection form for the channel segment in question and then totaling the resulting set of weighted item values for the segment.

Although not necessary, it is also most preferred that the standardized weighting multipliers account for the different scale ratings which are applicable to at least most of the items listed on the reach inspection form. It is also preferred that the determination of the standardized channel condition index value include the step of dividing the sum of the weighted item values for the channel segment by the length of the channel segment.

As will be understood, the standardized weighting multipliers employed in the inventive method reflect the relative significance of the various items listed on the inspection form and preferably also account for the different scale ratings applied thereto. Thus, the resulting standardized channel condition index value for each channel segment is representative of the relative overall condition of the channel segment as well as the significance of the particular inventory elements pertaining thereto. Table X provides an example of a standardized set of weighting multipliers which might be used for the inventory items set forth on the standardized inspection form.

TABLE X Example Of Standardized Weighting Multipliers For Inspection Form Elements Number of Adjacent Overbank Properties Affected by Channel Condition MULTIPLIERS Slightly Moderately Highly Affected Affected Affected Houses 25 50 100 Apartments Condo Buildings 25 50 100 Detached Garages/Out Buildings 10 20 40 Yards 10 20 40 Fences 5 10 20 Other Appurtenances 5 10 20 Commercial/Industrial Buildings 25 50 100 Public Buildings 25 50 100 Other Buildings 25 50 100 Parking Lots 10 20 40

Number of Infrastructure Items Affected by Channel Conditions MULTIPLIERS Not Slightly Moderately Highly Affected Affected Affected Affected Side Headwall/Outfall 0 1 2 4 Weir/Blocks/Drop 0 1 2 4 Roadway (LF) 0 1 2 4 Bridge Abutment 0 10 20 40 Bridge Pier 0 10 20 40 Culvert Wingwall 0 1 2 4 Culvert Apron/End 0 1 2 4 Pipe Culvert 0 10 20 40 Low Water Crossing 0 10 20 40 Other Structure 0 1 2 4

MULTIPLIERS Public Utilities Sanitary Sewer Line Exposed 2 # of San. Sewer Manholes Exposed 2 Water Line Exposed 2 Private Utilities # of Gas Line Exposures 1 # of Electric Line Exposures 1 # of Other Util. Exposures 1

Channel Conveyance Condition MULTIPLIERS # of Trees with Exposed Roots 1 # of Trees in Immediate Danger of Falling 2 # of Trees Down in Channel 4 MULTIPLIERS Slight Moderate Severe Trees/Brush/Undergrowth Impeding Flow 1 2 4 (LF) Drift Accumulation Impeding Flow (LF) 1 2 4 Bank Erosion/Scour (LF) 1 2 4 Bottom Scour (LF) 1 2 4 Sediment Deposition (LF) 1 2 4

Improved Channel Condition (LF) MULTIPLIERS Good Slight Moderate Severe Condition Defects Defects Defects Concrete Side Slopes 0 1 2 4 Concrete Bottom 0 1 2 4 End of Concrete Channel 0 1 2 4 Trickle Channel 0 1 2 4 Rip Rap 0 1 2 4 Rip Rap, Grouted 0 1 2 4 Gabion 0 1 2 4 Interlocking Blocks 0 1 2 4 Fabric Formed Concrete 0 1 2 4 Retain Wall, Concrete 0 1 2 4 Retain Wall, Masonry 0 1 2 4 Retain Wall, Timber 0 1 2 4 Other 0 1 2 4

As will be understood by those in the art, the weighting multipliers employed in the inventive method for calculating standardized channel condition index values from the inventory data can be derived using factors such as the relative costs for servicing, repairing, or replacing the items in question, the item conditions, (e.g., slight, moderate, severe, etc.), the relative effect of the items on flow conditions, the relative urgency of the items based upon other factors such as typically rates of further deterioration, effects on adjacent properties, utilities, etc., or any other factors, history, experience, etc., available.

By way of example, Table XI demonstrates the calculation of the standardized channel condition index value of a particular channel segment. The segment is 920 feet in length and it has been determined using the standardized inspection procedure that the reach includes the following items: 5 trees with exposed roots; 30 linear feet of slight bank erosion/scour; 10 linear feet of moderate bank erosion/scour; 400 linear feet of slight bottom scour; 900 linear feet of slight tree/brush/undergrowth impeding flow; and 20 linear feet of slight drift accumulation impeding flow. Using the standardized weighting multipliers set forth in Table X, the weighted total for all of the inventory items identified for this channel segment is 1375. This value is preferably divided by the total length of the segment to yield a standardized channel index value of 1.495.

TABLE XI Example Calculation Of The Standardized Channel Condition Index Value For A Channel Segment Item Value Multiplier Total # of Trees with Exposed Roots 5 1 5 Bank Erosion/Scour - Slight (LF) 30 1 30 Bank Erosion/Scour - Moderate (LF) 10 2 20 Bottom Scour - Slight (LF) 400 1 400 Trees/Brush/Undergrowth Impeding 900 1 900 Flow - Slight (LF) Drift Accumulation Impeding 20 1 20 Flow - Slight (LF) Total Condition 1375 Segment Length 920 Standardized Channel Segment Condition 1.495 Index Value

As mentioned above, in addition to providing significant assistance and direction for identifying and prioritizing needed service, maintenance, and improvement projects, the inventive method can also greatly assist the community or other entity in more accurately and thoroughly mapping its storm water or other open channel systems. The geometry or line representations of the creeks or other channels can be input from a variety of sources. CAD software packages such as AutoCAD or MicroStation, or a geographic information system (GIS) package such as ArcGIS or Geomedia, are well suited for inputting this information. At the beginning of the project, or when adding new reaches or segments, one way to start is to obtain a digital detailed creek network from a municipal website or through the local government's GIS or engineering office. Another method is to obtain aerial photos or USGS topographical maps of the area and digitize the creeks to be studied (using, e.g., CAD or GIS).

In order to identify each creek within the database, a naming convention of the type described above will preferably be used. Many creeks have drainage basins associated with them that can be used to subdivide the creek into segments. These basin networks can be used to name the creeks according to the procedure described. As noted, further subdivisions may typically be made based upon channel conditions in the field. It is also important to provide clear guidelines to the field inspector for naming the segments being studied in the survey.

Once the base creek mapping has been laid out, the field mapping can begin. GIS lends itself well to setting up the field maps for this task because of its ability to make indexed map books. Map scales ranging from 1:100 to 1:200 are typically appropriate for the level of detail needed to adequately inventory segment conditions. These maps can show the part of the channel being surveyed with the overall channel stationing and other features to help guide the surveyor. The channel stationing may also be used as an aid for estimating lengths in the field. Utility locations, floodplain extent, street names, and drainage boundaries can help the surveyor determine his location on the map and therefore the stationing of the upstream and downstream ends of the channel segments.

After the field work is complete, and the maps have been annotated to illustrate the breaks and the different types of channels, the data can be converted to a GIS format. The beginning stages of generating the data for the channel inventory can be done, for example, in CAD or GIS. GIS databases are preferred for properly connecting the creek geometry on the map with the channel management system database records for custom map creation. Most GIS software can readily import CAD data and then convert it to the native format of the GIS software. Once the data is in GIS format, each segment that has been detailed in the channel management system database will preferably have its own line segment with a segment I.D. in the attribute table that matches the flood management area and the segment I.D. in the channel management system database.

For each channel segment, there will preferably be a line in the GIS file containing a link that matches a record to the CMS database. For example, if the channel segment is listed in the CMS database as SC-01-B, the geometry will preferably have a single creek segment with an attribute that matches that identification. Most GIS software packages will allow for a joining of the data between the shape file geometry and an outside database via a dynamic link which will correspond to the flood management area and the channel segment identification. In the GIS, the creek segments can be queried and information about the channel from the separate CMS database can be viewed. Changes made to the database can be recognized in the GIS once the geometry is queried.

In the form view of the CMS database, there will preferably be a snapshot of the channel segment geometry with an aerial photo behind it. In order to generate these snapshots, a channel segment map-book can be created. By way of example, this data can be built using the map-book function in ArcGIS by the steps of: buffering each segment by one foot to create a polygon layer that contains the attributes of the segment; using the polygon layer to create an index layer for the map-book; adding aerial photos and other snapshots to the ArcGIS project; setting up the ArcGIS with a map-book to export a named JPG format image for each segment in the database using the flood management area and channel segment identification; and organizing these images by basin and placing them in a folder entitled “Channel Segment Locator” under their respective creeks.

In addition to the creek identification in the GIS data, other attributes of the channel segment can be incorporated into the geometry's associated table. For example, if a municipality wants the ability to determine which channel segments would be part of future capital investment projects, each channel segment located in a current or proposed capital improvement can be given a link to the named project as an attribute. In addition to the relevant attributes, photos taken in the field can be attached to the GIS data to allow for a quick link to the pictures from the GIS software.

Also in accordance with the present invention, the detailed data generated by the inventive inspection and evaluation method can be incorporated in and visualized as a part of the system mapping using GIS. Live links can be established for viewing the standardized channel condition values as part of the GIS mapping. For example, ranges of standardized channel condition index values can be color coded to distinguish which channel segments are in the best or worst condition. For example, channel segments which are in poor condition and therefore have a standardized channel condition index value of greater than 7 can be shown in red. Channel segments which have standardized channel index values in the range of from 4 to 7 and are therefore in fair condition can be shown in yellow. Finally, channel segments which have standardized channel condition index values of less than 4 and are therefore in good condition can be shown in green.

Thus, the present invention is well adapted to carry out the objects and attain the ends and advantages mentioned above as well as those inherent therein. While presently preferred embodiments have been described for purposes of this disclosure, numerous changes and modifications will be apparent to those in the art. Such changes and modifications are encompassed within the spirit of this invention as defined by the claims. 

1. A method of managing a system of open channels for channel evaluation, servicing said open channels, maintaining said open channels, improving said open channels, or a combination thereof, said method comprising the steps of: (a) dividing said system of open channels into a plurality of channel segment lengths for evaluation; (b) conducting for each said channel segment length an inventory based upon a standardized set of items to identify any and each of said items existing in said channel segment length; and (c) determining a standardized channel condition index value for each said channel segment length based upon said items existing in said channel segment length.
 2. The method of claim 1 wherein: said method further comprises the step of assigning ratings to at least a portion of said items existing in said channel segment lengths based upon standardized ratings scales and said standardized channel condition index value determined in step (c) for each said channel segment length is based upon said items existing in said channel segment length and said ratings assigned to said portion of said items.
 3. The method of claim 2 wherein said step of determining said standardized channel condition index value for each said channel segment length further includes applying standardized weighting multipliers to said items existing in said channel segment length to provide a set of weighted item values for said channel segment length.
 4. The method of claim 3 wherein said standardized weighting multipliers applied to said portion of said items are dependent upon said ratings assigned to said portion of said items.
 5. The method of claim 4 wherein said step of determining said standardized channel condition index value for each said channel segment length further comprises calculating a total of said set of weighted item values for said channel segment length.
 6. The method of claim 5 wherein said step of determining said standardized channel condition index value for said channel segment further comprises dividing said total of said set of weighted item values for said channel segment length by a length of said channel segment length.
 7. The method of claim 1 wherein said step of determining said standardized channel condition index value for each said channel segment length further includes applying standardized weighting multipliers to said items existing in said channel segment to provide a set of weighted item values for said channel segment length.
 8. The method of claim 7 wherein said step of determining said standardized channel condition index value for each said channel segment length further comprises calculating a total of said set of weighted item values for said channel segment length.
 9. The method of claim 8 wherein said step of determining said standardized channel condition index value for said channel segment further comprises dividing said total of said set of weighted item values for said channel segment length by a length of said channel segment length.
 10. The method of claim 1 further comprising the step of ranking said channel segment lengths according to said standardized channel condition index values determined for said channel segment lengths in step (c).
 11. The method of claim 1 wherein said standardized set of items comprises at least one natural channel condition.
 12. The method of claim 11 wherein said natural condition is an erosion condition.
 13. The method of claim 11 wherein said natural condition is a tree, brush, or undergrowth condition.
 14. The method of claim 1 wherein said standardized set of items comprises at least one channel improvement condition.
 15. The method of claim 1 wherein said standardized set of items comprises at least one adjacent overbank properties condition.
 16. The method of claim 1 wherein said standardized set of items comprises at least one infrastructure condition.
 17. The method of claim 1 wherein said standardized set of items comprises at least one utilities condition.
 18. A method of managing a system of open channels comprising the steps of: (a) dividing said system of open channels into a plurality of channel segment lengths; (b) conducting for each said channel segment length an inventory based upon a standardized set of items to identify any and each of said items existing in said channel segment length; and (c) assigning ratings to at least a portion of said items existing in said channel segment lengths based upon standardized ratings scales and instructions.
 19. The method of claim 18 wherein said standardized set of items comprises at least one natural channel condition.
 20. The method of claim 19 wherein said natural channel condition is an erosion condition.
 21. The method of claim 19 wherein said natural channel condition is a tree, brush, or undergrowth condition.
 22. The method of claim 18 wherein said standardized set of items comprises at least one channel improvement condition.
 23. The method of claim 18 wherein said standardized set of items comprises at least one adjacent overbank properties condition.
 24. The method of claim 18 wherein said standardized set of items comprises at least one infrastructure condition.
 25. The method of claim 18 wherein said standardized set of items comprises at least one utilities condition. 